https://phaidra.vetmeduni.ac.at/o:5619 Extracellular vesicles as indicators of environmental stress response in Lactiplantibacillus plantarum Razim, Agnieszka Agnieszka Razim 0000-0001-5471-7013 Laimer-Digruber, Astrid Astrid Laimer-Digruber 0000-0002-8809-2530 University of Veterinary Medicine Vienna. Centre of Pathobiology Schmid, Anna M. Anna M. Schmid 0009-0008-6432-7009 Edelbacher, Tanja V. Tanja V. Edelbacher 0009-0004-6640-0346 University of Veterinary Medicine Vienna. Centre of Pathobiology Paschall, Magdalena E. Magdalena E. Paschall Weinmayer, Tamara Tamara Weinmayer 0009-0006-6223-8083 Thaler, Michael Michael Thaler 0009-0007-3080-7525 Kebreab, Rim Rim Kebreab Skalska, Magdalena E. Magdalena E. Skalska 0000-0003-0069-0550 Migdał, Paweł Paweł Migdał 0000-0002-2615-9760 Morandi, Mattia Mattia Morandi 0000-0001-8467-4552 Daniel, Catherine Catherine Daniel 0000-0002-5299-2799 Srutkova, Dagmar Dagmar Srutkova 0000-0003-0054-5396 Schwarzer, Martin Martin Schwarzer 0000-0002-1401-6578 Hrdy, Jiri Jiri Hrdy 0000-0003-0612-4509 Ehling-Schulz, Monika Monika Ehling-Schulz 0000-0001-7384-0594 University of Veterinary Medicine Vienna. Centre of Pathobiology Górska, Sabina Sabina Górska 0000-0002-3206-0695 Inic-Kanada, Aleksandra Aleksandra Inic-Kanada 0000-0001-7854-3812 Wiedermann, Ursula Ursula Wiedermann 0000-0002-1302-3223 Schabussova, Irma Irma Schabussova 0000-0002-2109-2640 OAE Publishing journal article open access eng Aim: To determine how exposure to bile influences the production, physicochemical properties, and molecular composition of extracellular vesicles (EVs) released by the probiotic Lactiplantibacillus plantarum (L. plantarum) NCIMB 8826. Methods: L. plantarum cultures were incubated with and without a physiologically relevant cocnentartion of bile. EVs were isolated by ultracentrifugation followed by size-exclusion concentration (SEC) and characterized per Minimal Information for Studies of Extracellular Vesicles guidelines. Assessments included purity [protein and peptidoglycan (PGN) content], particle size distribution, zeta potential (ZP), lipid profiling, stability assays under varying pH, ionic strength (NaCl) and detergent challenge, Fourier-transform infrared spectroscopy (FTIR), and proteomic analysis were performed. Comparisons were made between purified EVs and parent bacterial cells, and between EVs from bile-exposed and control conditions. Results: SEC markedly reduced copurifying proteins and PGNs, improving EV compositional purity. Purified L. plantarum EVs (LpEVs) displayed surface lipid profiles and ZP that were distinct from parent cells and maintained stability across a range of pH values, elevated NaCl, and low detergent concentrations. Bile exposure induced release of larger LpEVs enriched in proteins involved in bile metabolism. FTIR detected bile-induced molecular changes in LpEVs that differed from alterations observed in whole bacterial cells. Conclusion: L. plantarum modulates EV size and cargo in response to bile stress, producing stable, compositionally distinct vesicles enriched in bile salt hydrolase. These findings indicate that bacterial EVs act as dynamic responders to environmental stress and may mediate early host–microbe communication prior to detectable cellular changes. EVs probiotics stress gut environment bacterial communication Fourier-transform infrared spectroscopy ultracentrifugation http://creativecommons.org/licenses/by/4.0/ https://phaidra.vetmeduni.ac.at/api/object/o:5619/download 10.20517/evcna.2026.26 https://phaidra.vetmeduni.ac.at/o:605 application/pdf Extracellular Vesicles and Circulating Nucleic Acids issn:2767-6641 VoR Extracellular Vesicles and Circulating Nucleic Acids 7 2 11.09 MB 2026